Abstract
Does genetic variation in the insulin/insulin-like growth factor signaling pathway (IIS) underlie latitudinal life-history clines in North American Drosophila melanogaster? Durmaz et al. investigated how a clinally varying polymorphism in the IIS gene foxo affects fitness-related traits by isolating the effects of alternative low and high latitude alleles. The phenotypic effects of the polymorphism-for example, on body size-matched those normally observed across the cline, suggesting that variation in IIS is important for clinal life-history adaptation.
